between wind and water

Vulnerable. She's between wind and water, living in this terrible neighborhood. I hope she moves soon, for her own safety. What are you thinking walking around here alone and unarmed in the middle of the night? You're completely between wind and water! Once news of the scandal breaks, you'll be between wind and water. There's no way you'll avoid attacks from the candidate running against you.

between wind and water

at a vulnerable point.

This is a nautical metaphor referring to the part of a ship's side near the waterline that is sometimes above the water and sometimes submerged; damage to the ship at this level is particularly dangerous. The phrase is first recorded in its literal sense at the time of the Spanish Armada ( 1588 ): ‘One of the shot was betweene the winde and the water, whereof they thought she would haue sonke’. By the mid 17th century, it was also being used of people.

1967 Michael Gilbert The Dust and the Heat Mallinson must have guessed what was coming. Nevertheless, it hit him between wind and water.